To elaborate on a feature
ZenGarden is hitting on in this particular instance, I personally find that outside of the guide and your phone for hints/achievement status/etc.,
THE MOST VALUABLE SOURCE OF DATA/INFO IS KNOWING THE GIRL'S LOCATIONS. You get this info by hacking the girls' subdermal implants.
THE PROCESS TO HACK THE GIRL'S SUBDERMAL IMPLANTS IS ALL IN THE GUIDE.
Once you hack any girl's implant, you have access to a lot of other add'l info but location, location, location tells you where you can find them and this aids in knowing what you can do w/them and when. Rather than grind around waiting for X-girl to be in X-location, now you know where they are and when. Depending on the location and the window you need for a specific task, sometimes you can find a girl and "put them" where you want simply by asking to meet you, at the bar, the pool, the gym, etc.
In my opinion, its the single most "grind-eliminating", genius feature in the game. It can be time consuming to hack ALL the girls' implants but if you prioritize your favorites, it goes by pretty quickly in the background while you're doing other things. So hack away. It will make your life and game-experience much more efficient.